#include "module.h" #include "lauxlib.h" #include "platform.h" #include #include #include "user_interface.h" #include "pixbuf.h" static inline uint32_t _getCycleCount(void) { uint32_t cycles; __asm__ __volatile__("rsr %0,ccount":"=a" (cycles)); return cycles; } // This algorithm reads the cpu clock cycles to calculate the correct // pulse widths. It works in both 80 and 160 MHz mode. static void ICACHE_RAM_ATTR tm1829_write_to_pin(uint8_t pin, const uint8_t *pixels, size_t length) { const uint8_t *p, *end; uint8_t phasergb = 0; p = pixels; end = p + length; const uint32_t t0l = (1000 * system_get_cpu_freq()) / 3333; // 0.390us (spec=0.35 +- 0.15) const uint32_t t1l = (1000 * system_get_cpu_freq()) / 1250; // 0.800us (spec=0.70 +- 0.15) const uint32_t ttot = (1000 * system_get_cpu_freq()) / 800; // 1.25us while (p != end) { register int i; register uint8_t pixel = *p++; if ((phasergb == 0) && (pixel == 0xFF)) { // clamp initial byte value to avoid constant-current shenanigans. Yuck! pixel = 0xFE; } if (++phasergb == 3) { phasergb = 0; } ets_intr_lock(); for (i = 7; i >= 0; i--) { register uint32_t pin_mask = 1 << pin; // Select low time register uint32_t tl = ((pixel >> i) & 1) ? t1l : t0l; register uint32_t t1, t2; register uint32_t t = _getCycleCount(); t1 = t + tl; t2 = t + ttot; GPIO_REG_WRITE(GPIO_OUT_W1TC_ADDRESS, pin_mask); // Set pin low while (_getCycleCount() < t1); GPIO_REG_WRITE(GPIO_OUT_W1TS_ADDRESS, pin_mask); // Set pin high while (_getCycleCount() < t2); } ets_intr_unlock(); } } // Lua: tm1829.write(pin, "string") // Byte triples in the string are interpreted as GRB values. static int ICACHE_FLASH_ATTR tm1829_write(lua_State* L) { const uint8_t pin = luaL_checkinteger(L, 1); const uint8_t *pixels; size_t length; switch(lua_type(L, 3)) { case LUA_TSTRING: { pixels = luaL_checklstring(L, 2, &length); break; } case LUA_TUSERDATA: { pixbuf *buffer = pixbuf_from_lua_arg(L, 2); luaL_argcheck(L, pixbuf_channels(buffer) == 3, 2, "Bad pixbuf format"); pixels = buffer->values; length = 3 * buffer->npix; break; } default: return luaL_argerror(L, 2, "String or pixbuf expected"); } // Initialize the output pin and wait a bit platform_gpio_mode(pin, PLATFORM_GPIO_OUTPUT, PLATFORM_GPIO_FLOAT); platform_gpio_write(pin, 1); // Send the buffer tm1829_write_to_pin(pin_num[pin], pixels, length); os_delay_us(500); // reset time return 0; } LROT_BEGIN(tm1829, NULL, 0) LROT_FUNCENTRY( write, tm1829_write ) LROT_END(tm1829, NULL, 0) int luaopen_tm1829(lua_State *L) { // TODO: Make sure that the GPIO system is initialized return 0; } NODEMCU_MODULE(TM1829, "tm1829", tm1829, luaopen_tm1829);